


Prosperous

by La_Temperanza



Category: Merlin (TV)
Genre: Alternate Universe - Canon Divergence, Lactation Kink, M/M, Mpreg, Pregnant Sex, Rimming
Language: English
Status: Completed
Published: 2013-05-13
Updated: 2013-05-13
Packaged: 2017-12-11 19:05:44
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,826
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/802133
Author URL: https://archiveofourown.org/users/La_Temperanza/pseuds/La_Temperanza
Summary: <blockquote class="userstuff">
              <p>Arthur and Merlin spend some alone time together while they still can. Because apparently, Merlin's magic made them <i>both</i> extremely fertile.</p>
<p>For this KMM prompt: <i>mpreg, pregnant sex, both of them pregnant with the other's child, one of them is much farther along, while the other is just starting to show, maybe the second pregnancy was an accident?</i></p>
            </blockquote>





	Prosperous

**Author's Note:**

> First time writing mpreg, but I couldn't resist the prompt. Thanks to bloodsongs for looking this over for me.

One of the problems with sorcerers, Arthur has come to realize, is that they are too damn fertile.

You would think the issue would be mentioned once or twice during his father's crusade against all things magical. It would explain why no matter how many people Uther had burned, or beheaded, or hanged, that sorcery and those who practiced it never fully died out. Apparently, their secret to survival was just to reproduce like rabbits. Constantly.

Those days of persecution are long gone, and an era of peace has spread throughout Camelot and the rest of Albion in the years under Arthur's reign. But the will to pass their seed down through the ages must have become an innate part of themselves; even after their beliefs and lives were no longer under threat, the rate of children being sired to those with magic continue to grow by the day.

It would certainly explain how his ex-servant, newly appointed Court Sorcerer, and Prince Consort managed to get himself pregnant, despite the fact that Merlin was most definitely _male_. Arthur had it confirmed, many times, the night the two of them created a new life together amidst the kissing of swollen bruised mouths and sliding of sweat-slicked skin. And a few months later, when Merlin had shoved him against the wall and taken him from behind, too eager that his morning sickness was finally gone to make it to the bed, Arthur learned that unnatural fertility didn't just affect those with magic.

Or maybe it did, usually. Maybe it's just Arthur's luck that he bedded with the supposed greatest sorcerer that ever lived, the same sorcerer who could trip over air, who could lose balance of a platter even whilst standing perfectly still, or could impregnate the King of Camelot without realizing it.

It bothered him at first. Merlin would no doubt say "bothered" is putting it mildly; for the first few weeks after Arthur found out, he was positively livid. He was a king, he argued, and should not be burdened with such trivial things such as pregnancy and childbirth when he had more important issues to be concerned with, such as running the kingdom.

Not surprisingly, Merlin was unsympathetic to Arthur's plight. He had apologized profusely for not knowing his magic was capable of getting them both pregnant, but rolled his eyes every time Arthur complained about aches and pains, and how the whole thing was beneath someone of his stature.

Until one day, Merlin had enough. He had traveled with Arthur to the battlefield, even though Arthur had insisted Merlin should have stayed behind in the safety of the citadel.

"For gods’ sake, I'm not an invalid, you prat," he snapped, storming out of their tent despite Arthur's protests that Morgana's army was closing in. "Just because I'm pregnant doesn't mean I'm weak, nor does it mean I can no longer fight for you. Watch."

Merlin's eyes went gold, and his arm stretched out in the direction of the opposing forces. With a few whispered words, the ground beneath them began to tremble, and Morgana's men were flung into the air like rag dolls. Within seconds, the entire thing was over, and while they might have not won the war that day, there was no doubt that they won the battle, hands down.

"Do you see?" Merlin asked, turning back to Arthur, his eyes still burning with magic. He snatched Arthur's hand and pressed it against the forming bulge of his stomach. "I'm pregnant with your child-- _our child_ \--and I still can protect you and this kingdom, just like I always have. So don't think you're any less of a man because you carry a life inside of you as well."

Arthur swallowed, in awe by Merlin's display of magic and the truth behind his words. He had drawn Merlin in close, whispering his apologies for suggesting otherwise. And if it turned out Merlin practically collapsed from exhaustion and was sentenced to bedrest for three days afterwards, Arthur was smart enough not to say anything about it.

Now, Arthur has grown to appreciate the situation, and works around any problems he might run into along the way. He still trains with the knights, though he keeps the sessions shorter, and mostly watches from the sidelines to call out his advice. He notices that they're all mindful not to land any blows to his stomach, even if his growing bump is hidden under a layer of chainmail. His thighs have already grown thicker though, stockier, and his hips have widened. His breeches will need to be let out again soon, and another hole added to his belt.

But he doesn't care, not when he enters his chambers and is immediately set upon by a very excited Merlin. "I missed you this morning," he breathes into Arthur's ear, trying to cling to Arthur's side, but the girth of his belly gets in the way. He constantly whines about feeling huge and bloated nowadays, but Arthur loves seeing the sharp angles of Merlin's body soften as his pregnancy progresses.

According to Gaius's calculations, Merlin has at least two months to go, and while Merlin can't wait, Arthur can't help but be saddened by the fact that he can only enjoy this for a little while longer. "Oh yeah?" he asks, taunts, as he runs his hands over the swell of Merlin's stomach. "Why don't you show me how much?"

Merlin moans and presses into Arthur's touch, and then tugs him towards the bed. The bed curtains part automatically, the sheets folding themselves out of the way, and Arthur is given a moment to think on how useful magic can be before he's shoved down onto the mattress.

"Missed you so much," Merlin says as he straddles himself across Arthur's lap. He's always careful not to put his full weight down, even though Arthur insists that a strong gust of wind could knock Merlin over, heavily pregnant or not. "If I wasn't so tired lately, I would have made my way down to the training grounds to watch you."

Arthur bites his tongue. He doesn't want to ruin the moment by saying that he's glad Merlin stayed in the chambers and rested. It's not that he thinks Merlin isn't capable of making such a short trip, but simply because he gets worried that the idiot doesn't know how to take care of himself. "You've seen me fight before, _Mer_ lin."

"Mm, but I love watching you every time," Merlin says, rocking his hips slightly against Arthur's. "I wanted to watch you get all hot and sweaty, and then afterwards I was going to take you into the armoury and lick every inch of your skin."

Arthur groans, and closes his eyes. Imagines it: the two of them alone in the shadows of an alcove, Arthur stripped from his chainmail, Merlin on his knees. "Fuck, Merlin, your _mouth_."

"You'd like that, wouldn't you? For me to take you in my mouth and suck you dry?" Merlin asks, his voice close to a purr. "Remember when we discovered how that helped me from getting sick in the mornings? Even when I wasn't feeling ill any more, I loved the taste of you on my tongue, loved having a reminder of you on my lips for the rest of the day."

Gods, Arthur should have known better than leaving Merlin alone for too long. Merlin has always been an active participant in bed, but the hormones from the pregnancy seem to make him bolder, needier. He's almost insatiable when he gets like this, his normal reservations about asking for sex nearly non-existent.

"And then, after you're done crying my name as you come," Merlin whispers, wearing a cheeky smile, "I would lick my way into your hole, get you so wet, make you beg for more, even after coming so soon."

That's it, Arthur can't take it any more. He flips their positions around until Merlin's on his hands and knees, his butt in the air. Merlin hasn't changed out of nightshirt yet (probably because he thinks breeches are too confining against his stomach), so Arthur is greeted with the sight of bare, pale skin. "You mean like this?" he asks, and then swirls Merlin's hole with his tongue before plunging it in.

"Ah!" Merlin cries out. "Yes, yes, Arthur, like that, _fuck_!"

Arthur hums as he works, spreading the cheeks of Merlin's ass farther apart. He knows how to lick, how to suck, how to make a babble of incomprehensible words stream from Merlin's mouth. His cock strains against the fabric of his breeches, and twitches at the maddening sounds Merlin's making. Pulling away, he wipes his mouth with the back of his hand before leaning over and shoving two fingers into Merlin's face. "Get them wet for me."

Merlin obliges, taking Arthur's fingers in and swirling his tongue around the knuckles. Arthur feels like he could come from that alone if he's not careful, and sneaks his other hand underneath Merlin's undershirt. He starts at the chest area, cupping the softness that's bloomed there during pregnancy, and thumbs a nipple until it becomes hard and erect under his ministrations. He pinches it lightly, and is rewarded when he feels a drop of moisture leak onto his fingertips.

"Fuck," Merlin breathes, letting Arthur's fingers slip from his mouth. "Arthur, don't tease."

"I can tease all I want," Arthur says, chuckling. He brings his hand from out underneath the shirt and licks the drop of milk off. It's sweet, warm, and Arthur finds himself craving more. But he'll have to satisfy that urge another day, before the first baby comes and he still has his chance. "I'm the king, remember?"

"You prat--" is all Merlin gets out before Arthur shoves a spit-slicked finger inside his hole. He keens in response, his muscles clenching around the digit, and his head falls forward.

"Shh," Arthur murmurs, rubbing the small of Merlin's back, tracing the knobs of his spine. "Relax."

"Don't treat me like one your stubborn horses, Arthur," Merlin says, but it comes half-hearted protest as he lets out another wanton moan. Arthur's finger sinks in farther into his heat, joined by the other, and together they move in and out, and then press against the bundles of nerves that would drive any man wild.

"A-arthur!" Merlin sobs, muffled as he buries his flushed face into the pile of pillows on the bed. His whole body shakes like a cord that's been pulled too tight. "Please, I can't..."

He doesn't finish his sentence, but he doesn't have to. Arthur understands. He's feeling the exact same way, like he's about to shatter into a thousand different pieces and left without a way to put himself back together again. He completes the following movements in swift succession of each other: he grabs the small vial from the side table drawer, tugs down his breeches far enough that his cock can spring forward, and coats himself liberally with oil. He yanks his fingers out, but before Merlin can mourn their loss, Arthur puts the tip of his erection against Merlin's glistening and puffy hole. "You ready?"

Merlin answers by pushing himself backwards onto Arthur's cock. Arthur gasps at the sudden action, and then groans as he slides in farther. "You're positively shameless, you know that?"

Merlin makes a little pleased noise as he jerks his hips in awkward, frantic motions. His belly limits his range of mobility, so Arthur takes control by gripping onto his hips and thrusting in with renewed purpose. They move in unison until they find their rhythm, the squelching sounds of their coupling echoing throughout the room.

One of Arthur's hands find their way back to Merlin's bump, rubbing circles across the stretched skin. He can't get enough of touching him like this, and thinks the sight of Merlin pregnant with his child is one of the most beautiful things he's ever seen. He would tell Merlin this, except Merlin would probably think Arthur was making fun of him, comparing him to a girl again. So Arthur remains silent, and is content in showing his adoration of Merlin's belly in other ways. He leans down, whispering the words he can't bring himself to say out loud into the sweaty skin of Merlin's back as he continues to stroke and caress.

His hand travels lower until it reaches Merlin's cock, stiff and leaking with pre-come. He swipes at the slit, wiping the liquid that beads there over the head and down the rest of the length before he takes the whole thing in his palm. He pumps it once, twice, until Merlin stiffens, and then lets out a sharp cry. His climax drips through Arthur's fingers and onto the sheets, and that's enough for Arthur to come as well, snapping his hips back one last time with a grunt. It takes a few seconds before can get his breathing under control, his softening cock slipping out easily as he sits back on his haunches.

The sight of semen and oil dribbling out of Merlin's hole and down the back of his thighs catches Arthur's attention, and though most of his energy is spent, he can't let the opportunity pass. He leans forward again and tries to clean it all up with his tongue, licking and sucking until Merlin pulls away, saying it's too much too soon.

"What happened to 'make you beg for more’'?" Arthur asks, smug with himself as he crawls up the bed, tucking Merlin’s trembling form into his arms.

"It doesn't count if I was going to do that to you," Merlin says, nuzzling into the warmth created by their bodies. “Maybe I’ll take you up on that offer later though.”

He seems exhausted, drawn out, and Arthur frowns. "Are you--"

"Arthur, if you ask if I'm okay, I'm going to turn you into a frog. Well, maybe not a frog, not while you're pregnant. But trust me, it won't be pleasant."

"I was just going to ask if you were cold," Arthur says lamely, not convincing anyone as his arms instinctively tighten around Merlin. It won't be much longer that they can sleep like this, with Merlin's back against Arthur's front. But he supposes once Merlin gives birth and Arthur gets bigger, they can switch positions. "I can get another blanket?"

"I'm fine. You forget that I can magic a fire up if we need one," Merlin says, his tone quiet and full of fatigue. For a second, Arthur thinks he's actually drifted off to sleep, until there's a well-placed kick under the spot Arthur's hand rests on, and Merlin sighs. "Great, it seems like someone's all wound up now."

Ever since the first time Merlin said he felt the baby move, Arthur's been entranced with the idea. He tucks his chin in the crook of Merlin's shoulder, watching as his hand shifts from the force of another kick. "What does it feel like?"

"Like a tiny person is kicking me from the inside," Merlin says with a dry chuckle. But even from this angle, Arthur can see the soft smile on his face, and knows Merlin gets a thrill from it as well. "I'm sure you'll find out soon enough. You're getting close to that time."

Arthur hums noncommittally. He thinks he's felt stirrings of something already, a fluttering underneath his diaphragm, but doesn't want to get too excited just yet. Because then the thoughts of his mother begin to infiltrate his mind, and the idea of losing Merlin, losing either one of the children, or them feeling the pain of losing him is all he can focus on. It hurts to the point of a physical ache in his chest, and keeps him awake at night even as Merlin snoozes by his side, unaware. He would share this fear, but is afraid of what Merlin would say if he ever found out.

No, that's not true. Because even though Merlin is a complete idiot at times, he's also one of the wisest and most understanding men that Arthur knows. There's no other person in this world who he'd confide his troubles in. Not any more at least.

"What about you?" Merlin asks, as if sensing Arthur's tension. And it's quite possible that he can; Arthur's never asked the full extent of his powers. He wonders if Merlin even knows. "Are you 'cold'?"

Arthur smiles at the double meaning, and places a kiss against Merlin's neck. Maybe he'll confess his fears one day, and tell Merlin exactly how much he means to him, if he hasn't guessed already. Maybe even tell him how beautiful he is, or how Arthur's grown to love being pregnant together.

But not today, when Arthur's basking in the glow of the two of them simply _being_ , after everything they've been through together. And that's enough to give him hope. "I'm fine. Just fine."


End file.
